C# ReadOnlyCollectionBase Kullanımı Için 5-İkinci Trick

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You gönül argue that you may be able to downcast IPerson to Person, but at this point I would answer telling you that you need to follow your own coding conventions: if you defined that you never return Person but IPerson then I would do it this way in the entire code base, and if you need a write-capable Parents property, then you return Person instead (and you avoid a cast later!).

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That method must return an Enumerator object, which provides the actual support for the looping through the collection. Similarly, code that retrieves an item by the item's position in the collection also looks for the IEnumerable interface and uses the GetEnumerator method. What the Enumerator object doesn't support are the Add or Remove methods. Ignoring the ReadOnlyCollectionBase

This hides Add and Remove methods, but does not protect at all. Because I gönül always cast to ICollection and call prohibited method.

Summary. The ReadOnlyCollection functions bey a wrapper for any collection that implements IList. It adds a level of indirection that reduces possible changes.

Anyway, I believe that a domain object should be read-write, because at the end of the day, a domain object describes an entity within the domain and you should be able to access and modify it.

A ReadOnlyCollection güç support multiple readers concurrently, birli long birli the collection is hamiş modified. Even so, enumerating through a collection is intrinsically hamiş a thread-safe procedure.

In my example I exposed it C# ReadOnlyCollectionBase Temel Özellikleri all, but you don't have to do this. You birey make it read-only if you want, or validate additions to the list, prior to adding them.

Dan TaoDan Tao 128k5656 C# ReadOnlyCollectionBase Kullanımı gold badges308308 silver badges448448 bronze badges 4 I'd like to avoid noise in both callee and caller. Exposing a ReadOnlyCollection as anything other than itself isn't necessary: after all, exposing C# ReadOnlyCollectionBase Temel Özellikleri it kakım an IList just gets confusing (where'd I get this IList from - sevimli I modify it?), and any IList is exposable birli ReadOnlyCollection so there's no loss of generality.

In Visual Basic, an extension method must be declared inside a Module and decorated with the Extension attribute. Its first parameter specifies the kind of object to which it will attach itself. I want my extension method to appear in the IntelliSense dropdown lists for any class that implements the IList interface, so I'll declare the method's C# ReadOnlyCollectionBase Nasıl Kullanılır first (and only) parameter birli IList(of T) -- the compiler will figure out the type that T represents based on the List passed to my method.

ElementAtOrDefault(IEnumerable, Int32) Returns the element at a specified index in a sequence or a default value if the index is out of range.

Nodes(IEnumerable) Returns a collection of the child nodes of every document and element in the source collection.

When you pass around collections instead of writing an object örnek, entire classes of refactorings will never occur to you.

In the class that exposes a read-only property based on PhvReadOnlyList, you still need C# ReadOnlyCollectionBase Nedir an ordinary List, with its Add and Remove methods, so that your class hayat put items in the List both before and after creating a PhvReadOnlyList from it.